Supported by

RESISTANCEREMOVING

Science, Technology and Engineering FocusST MSTST MEeEE

INTRODUCTION

The challengeUnderstand the principles of hovering by building your own craft that can glide effortlessly across the table.

Escaping air between two flat surfaces creates a thin cushion. This cushion of air dramatically reduces the friction between the CD and the surface allowing your hovercraft to move freely over a smooth surface.

Ever since Luke Skywalker went in search of R2-D2 in his land speeder in Star Wars: A New Hope and Marty McFly stepped on his hoverboard in Back to the Future 2, moviegoers have wanted to ride on air.

Magneto (the X-Men’s arch enemy) uses his mutant powers to suspend metal objects in the air to defy the laws of gravity.

How are these effects created? It’s not always CGI. This science and technology focused challenge will show you how it can be achieved.

CHALLENGE

Teams of two 60 minutes

2/3 KS2/3 Apprentice

MATERIALS

• Graphite levitation kit • A CD or DVD disc • A balloon • A pop-top cap from a liquid soap

bottle or a water bottle • A hot glue gun and needle

Lauren Elisabeth / Shutterstock.com

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1 Royal Academy of Engineering

The procedure1. Cover the centre hole of the CD with a piece of

tape and poke six holes in the tape with a needle. This will slow down the flow of air and allow your hovercraft to hover longer.

2. Use the hot glue gun to secure the cap to the centre of the CD or DVD disc. Create a good seal to keep air from escaping.

3. Blow up the balloon all the way and pinch the neck of it (don’t tie it).

4. Make sure that the pop-top is closed and fit the neck of the balloon over the pop-up portion of the cap (this is usually easier with two people).

5. That’s it! When you are ready to commence hovering, simply put the craft on a smooth surface and pop the top open.

6. Be creative and decorate your craft.

EXTENSION

1. Does the size of the balloon affect the CD’s ability to hover?

2. Does a helium balloon work better than an air-filled balloon?

3. Do larger discs make better hovercrafts (plastic picnic plates, old records)?

Watch American professional skateboarder Tony Hawk go back to the future and try out the latest hover board technology

www.youtube.com/watch?v=wCZiEtduSQg

The demonstrationYour teacher will show you how objects hover using the graphite levitation kit provided.

This contains a small sample of pyrolytic graphite, 16 small rare earth magnets, a steel base and a pair of tweezers.

When the magnets are arranged in a matrix on the base plate, the graphite will levitate just above the surface. This demonstration of diamagnetic behaviour involves the repulsion of the graphite by both the north and south of the magnets.

REMOVING RESISTANCE

Royal Academy of EngineeringPrince Philip House, 3 Carlton House Terrace, London SW1Y 5DG

Tel: +44 (0)20 7766 0600www.raeng.org.uk

Registered charity number 293074 Cover images: Shutterstock.com/iStockPhoto.com

Royal Academy of Engineering

As the UK’s national academy for engineering, we bring together the most successful and talented engineers for a shared purpose: to advance and promote excellence in engineering.

We have four strategic challenges:

Make the UK the leading nation for engineering innovation

Supporting the development of successful engineering innovation and businesses in the UK in order to create wealth, employment and benefit for the nation.

Address the engineering skills crisis

Meeting the UK’s needs by inspiring a generation of young people from all backgrounds and equipping them with the high quality skills they need for a rewarding career in engineering.

Position engineering at the heart of society

Improving public awareness and recognition of the crucial role of engineers everywhere.

Lead the profession

Harnessing the expertise, energy and capacity of the profession to provide strategic direction for engineering and collaborate on solutions to engineering grand challenges.

RESISTANCE